Drawing machine



Sept. 1, 1936. w. STAHL 2,052,904

DRAWING MACHINE I 3 Sheets-She'd 1 Filed March 8, 1955 67 as 4 4 K. 5 4o 21 1 56 47 n Q 46 8 2 34 5o 24 Inventor: W 8%46/ W. STAHL DRAWING MACHINE Sept. 1, 1936.

Filed March 8, 1935 :5 Sheets-Sheet 2 Inventor: W 53%;}

V g W1 Sept. 1, 1936. w. sTAHL DRAWING MACHINE Filed March 8, 1935 3 Sheets-Sheet 3 Inventor:

Patented Sept. 1, 1936 PATENT OFFICE DRAWING MACHINE Wilhelm Stahl, Lahr, Germany, assignor to the firm: Albert Nestler A.G., Lahr, Germany Application March 8, 1935, Serial No. 10,105 In Germany September 3, 1934 7 Claims.

The present invention relates to an apparatus forhatching drawings. The apparatus according to the invention is adapted for use in drawing machines of the kind at which the drawing head can be moved over the drawing paper or the drawing board into any desired position- By means of the novel apparatus the drawing head can be switched i. e. moved step by step in accordance with the. distance between the clashes -or streaks of the hatchings, by manipulating a switching device.

This switching or shifting is preferably performed bymeans of the main lever of the drawing head which controls the locking device. This involves the advantage, that all movements of the operative parts of the drawing head can be performed by means of a single lever. It is hereby of importance that all parts influencing the locking members proper are held arrested during the movements of the hatching device, so that the same are not'moved together with the said main lever.

"Two preferred constructional forms of the invention'are shown by way of examples in the accompanying drawings.

Fig. 1 isavertical section through the drawing head with the hatching apparatus in switched-off position.

"Fig. 2 is a bottom view of the drawing head 305i shown in Fig. 1;

'Fig. 3 ma vertical section through the drawing. head with the hatching device in switched-in position.

-.Fig.4 is a bottom view of the drawing head shown in Fig.-3.

Fig. 5 is-a vertical section throughthe drawing head after the line A-A in Fig. 2.

Fig. 6 is a vertical sectional view showing the switching device of the drawing head in inoperative position:-

'7 is a vertical sectional view showing a modified switching device in inoperative position.

Fig. 8is a vertical sectional view showing the switching device according to Fig. 6 in operative position. I I

:Fig. 9. is a vertical section after line. B-B in Fi 3. ig. 10"is a section after line C-C in Fig. 2. Onthe rails of a drawing machine a toothed disc I. is fastened by means of screws 2 (Figs. 2

and 4)} The disc I is formed with .a sleeve 3' which serves as'a pivot for a rule holder disc 4, the a'rmsiand 6 of which are adapted to receive thezrules or measuring ruleslnot illustrated).

The discs I and 4 form together with accessories the drawing head proper. The rule holder disc 4 is prevented from sliding off the sleeve 3 by means of a ring I and a set-screw 8. In a casing 9 rigidly connected to the rule holder disc 4 a bolt 5 I0 is fixed and this bolt is surrounded by a torsion spring I I the leg I2 of which presses against a pin I3 on an angle lever I4 and strives to turn this lever in clockwise direction on its pivot I5. The lower side of the rule holder disc 4 is formed 10 with a guide I6 in which a slide I7 is located which by the torsion spring II, under the intermediary of the arm I8 of the angle lever I4, is pressed radially against the toothed disc I, whereby a projection or finger I 9 on the slide I! is 15 pressed into a space between the teeth of the disc I and the rule holder disc 4 is held securely. against rotation. 7 When it is desired to alter the adjustment of the rule holder disc 4, this may be effected by means of the lever 20. This lever is rotatably arranged on the pivot I5 and normally rests with its lower side against a projection 2| on the angle lever I4. When the lever 20 is turned in the direction of the arrow L it will take the angle lever I4 along with it and the arm I8 of the latter lever will force the slide I! out of engagement with the toothing on the disc I. When the rule holder disc 4 by rotation has been brought into its new position and the lever 20 is released, the slide II will automatically slide back into a space between the teeth of the disc I (Figs. 1 and 2). If it, for adjustment of the rule holder disc 4 between two teeth of the disc I, is desired to keep the slide II out of engagement with the toothed disc I for a longer time or permanently, the lever 20 is moved in the direction of the arrow R. Hereby the upper end of the lever 22, which is located in the casing 9 on a pivot 23, is taken along with the lever 20 in the same direction, whereby simultaneously the lower arm I8 of the angle lever I4 is swung outward by the link 24 and the slide I1 is drawn out of engagement with the toothing of the disc I (Fig. 6). On the lower side of the rule holder disc 4 a clamping plate 89 is arranged, which contacts with the lower side of the toothed disc I and is formed or equipped with a pin 88, which projects into an aperture in the rule holder disc 4 (Fig. 10). A threaded pin 8|, which is rigidly fixed to the clamping plate 89, projects through an opening in the rule holder disc 4 and carries a nut with a finger grip 82. When the nut is drawn tight the toothed disc I and the rule holder. 55

On its lower surface the toothed disc I is.

formed with a boss 25 which in its centre hasa T-shaped groove 26 in which a slide or switching member 21 is located. This slide is. normally pressed against a stop 35 by one arm of 'a twoarmed spring 29 which is wound on a pin 28.

Perpendicular to the T-shaped groove 23. and:

parallel to the end face of the boss 25 a shallow groove 3| is formed in which two leaf springs 33 are located which by means of screws 32 are fixed to the lower side of the toothed disc I. Thefree ends of 'these springs serve as supports for the slide 21 and normally hold the same in such a position; that its corrugated lower side lies at a higher level than the. end face of the boss 25 (Fig. l). -In.the sleeve 3 another vertically displaceable sleeve 34 is arranged which at its lower end is formed with a slot 35 in which a pin 35 is fixed which serves as a-pivot for an angle lever 31! the downwardly directed arm 38 of which projects into an aperture..39 in the slide 21. At its upper end the sleeve-34 is formed with a flange 45 and between this flange and the ring 7 a pressure spring 4! is located which strives to hold the sleeve 34 at so high a level that a free intermediate space is formed between the upper surface of the slide 2'! and the lower end face. of thesleeve 34, so that the slide, if required, may slide freely (Figs. 1 and r In the sleeve34 a partially hollow plunger 42 .is slidably arranged and this plunger is formed with a finger 43 which, when the plunger is depressed, will engage the arm 44 of the angle lever 31. The. length of the stroke of the I plunger 42 is limited bya pin 45 which is passed through the massivepart of the plunger and which also prevents rotation of the plungerand the sleeve34. The pin' 45 is of such a length that it projects into the slots 46 and 4 1.- Between the plunger 42 and the sleeve 34- a pres-- sure spring 48 is locatedwhich strives to separate the plunger 42- and the sleeve 34. so that the-pin; 45 is pressedagainst the'upper end of the slots .41. Hereby the pressure spring 4 I which is weaker thanvthespring 48; will force the sleeve 34 upward together with all 'parts contained therein until the pin 45 is arrested at the-upper end ofthe slot 46 (Figs. 1 and 5) I a If now the. plunger 42 is depressed by a: force acting in the direction of the arrow P (Fig. 3)-- the spring .4 i. isv compressed. untiLthe flange 4!! of the sleeve 34contacts with the upper end of the sleeve 3, Simultaneously theslide 2Tis forced outward. by thelower end of the sleeve 34 against. the.

force of the leaf springs. 33 until the corrugated lower surface of the slide 2], (which slide has an ample play in the T-shaped groove. 26) protrudes over the lower end of the boss 25. Hereby the drawing head, which initially rested'onthedraw ing board with the lower end 'o'f*the's'le'e've 34, 'is lifted-so that the drawing head now only'rests on thedrawing board with 'the'corru'gated lower face of the slide '21." The slide 21 is lightly' clamped between the lower'end of the sleeve 34- and the leaf springs 33. If the: pressure ontheplunger- 42 is maintained in the direction of the arrow P, the spring 48 will be compressed and the finger 43 of the plunger 42 will move the angle lever 37 in clockwise direction whereby the drawing head, which rests on the drawing board with the slide 21, is forced to make a corresponding movement in the direction of the slide (Figs. 3 and 4).

If the pressure on the plunger 42 is removed the spring 48 will force the plunger upward until the pin 45 is arrested at'the upper end of the slots 41' in the sleeve 34. Thereupon the spring 4| will lift the sleeve 34 together with all parts contained'therein until the pin 45 also settles in the slots 45. During the last part of the movement of the sleeve 34 the slide 21 is forced back into the T-shaped groove 26 by the leaf springs 33 so that the drawing head again rests on the drawing board with the lower end of the boss 25. The spring29 thereupon forces the now fully released slide 2l back into its original position in which it is pressed against the stop 30.

The plunger 42 of the hatching'device is preferably actuated by the same lever .20 which is used for adjusting the drawing head, because in this case the position of the hand and the movement of the thumb will be the'same at all manip-' ulations .of the'drawing head.

In order that the parts of theadjusting or at resting mechanism remain inoperative during the hatching operation the lever 20 is moved to the right in the direction of the arrow R into ,the position shown in Fig. 6. In this position the arm 49 of the angle lever 50, which latter is pivotally arranged on the pin5lin the casing 9, can be swung past the nose 52' of the angle lever I4 in clockwisedirection. The tip lever 55, which p-ivotally arranged on the pin 54 fixedto the lever 53 partakes in this movement, whereby. the position of the tip lever 55 in the space is so altered influence of the torsion spring. ll be pressed against the lever arm 49 and in this position the angle lever l4 and also theangle lever 50 are held arrested. 51 denotes a tip lever which consists of three arms 59, and 52 and is carried by the pivot 58.fixed to the casing 9.. The arm 59 of this lever contacts with the plunger 42 whereas the arm '65 is situated above the.left' end of the tip lever 55. If now the lever 20 is moved in the di rection of the arrow Lthis movement is from the nose 56 transmitted to the plunger 42 over the tip levers 55 and 51. I 1 1 The length of'the stroke of the plunger or the distance between the lines in the hatchings is con-' trolled by means of a spiral disc 6| on which the arm'62 of theleveriilrests. The spiral. disc is rotatably arranged on a pivot 64 which is fixedto the plate 63. The plate 63 islocatedin a seat formed in the handlefifi and is fixed to the same by means of screws 65. The handle 66 itself is V fixedtothe rule holder disc 4 bymeansof screws ,Whenit is desired to bring the hatching device into its inoperative position and to re-establish the original conditions the lever .20 is first turned to the .right into the position shown in Fig. 6.

Hereby the nose 52 releases the lever arm .49 and the spring 68 on the. pin 5l-forces the angle lever 50 to the left into its position of rest. Thereupon,

the lever 20 is moved to the left in the direction of the arrow L, whereby all parts are brought back into the position shown in Fig. 1.

The Figs. 7 and 8 show a modified hatching device at which the slide 21 is replaced by a roller 61 having a toothed surface. This roller is ro tatably arranged on a pin 10 which is carried by the forked end of a yielding lever l I. One end of the forked lever 'H is together with a brake spring 12 fixed to the lower surface of the toothed disc I by means of a screw 13. In inoperative condition the other end of the lever ll rests on the bottom of the groove 14 in the boss 15. The brake spring [2 creates the necessary friction between the lever H and a segmental toothed lever 18 which is located in the sleeve 16 on apivot 11. In its position of rest the segmental lever 18 is pressed against a stop 86 by a torsion spring 19. The segmental lever is like the slide 21 actuated by the plunger 42.

When the plunger 42 is depressed the segmental lever engages the toothing of the roller 69 and forces the latter out of the boss 12, so that the drawing head thereupon rests on the drawing board with the roller 69. During the continued movement of the plunger 42 the roller 69 is rotated, whereby the drawing head is displaced correspondingly.

Further embodiments, modifications and variations may be resorted to within the spirit of the invention as here claimed.

I claim:

1. In the drawing head of a drawing machine, in combination, a rule holder, means for adjusting said rule holder, other automatically operating means for locking the rule holder in the adjusted position, a hatching device comprising a switching mechanism for moving the drawing head a predetermined distance corresponding to the chosen distance between the lines of the hatching, and still other common means for actuating said adjusting means and said hatching device.

2. In the drawing head of a drawing machine, in combination, a rule holder, means for adjusting said rule holder, other automatically operating means for locking the rule holder in the adjusted position, a hatching device comprising a switching mechanism for moving the drawing head a predetermined distance corresponding to the chosen distance between the lines of the hatching, and a single lever for actuating said adjusting means and said hatching device.

3. In the drawing head of a drawing machine, in combination, a rule holder, means for adjusting said rule holder, other automatically operating means for locking the rule holder in the adjusted position, a hatching device, comprising a spring-supported switching member, the lower surface of which normally lies in a higher horizontal plane than the lowermost surface of the rule holder, an axially displaceable sleeve arranged within the drawing head, operating means for the switching member arranged in said sleeve, a spring-controlled plunger for actuating said switching member, a spring for holding said sleeve in raised position, and a single lever for actuating said adjusting means and said hatching member.

4. In the drawing head of a drawing machine, in combination, a rule holder, means for adjusting said rule holder, other automatically operating means for locking the rule holder in the adjusted position, a hatching device, for moving the drawing head a predetermined distance corresponding to the chosen distance between the lines of the hatching, a single lever for actuating said adjusting means and said hatching device, said hatching device comprisng a switching member,

a plunger adapted to bring the switching member into engagement with the paper, and to move the drawing head over the predetermined distance, and an intermediate lever system for transmitting the movements of said lever to the said plunger.

5. In the drawing head of a drawing machine, in combination, a rule holder, means for adjusting said rule holder, other automatically operating means for locking the rule holder in the adjusted position, a hatching device, for moving the drawing head a predetermined distance, a single lever for actuating said adjusting means and said hatching device, said hatching device comprising a switching member, a plunger adapted to bring the switching member into engagement with the paper and to move the drawing head the predetermined distance, an actuating lever for said plunger, and adjustable means for controlling the movement of said actuating lever.

6. In the drawing head of a drawing machine, in combination, a rule holder, means for adjusting said rule holder, other automatically operating means for locking the rule holder in the ad- 5 justed. position, a hatching device, for moving the drawing head a predetermined distance, a single lever for actuating said adjusting means and said hatching device, said hatching device comprising a switching member, a plunger adapted to bring the switching member into engagement with the paper and to move the drawing head the predetermined distance, an actuating lever for said plunger, and a rotatable disc with a spiral-shaped edge for controlling the movement of said actuating lever.

7. In the drawing head of a drawing machine, a rule holder, means for adjusting said holder, a hatching device, means for operating said adjusting means as well as said hatching device, and an interlocking lever system adapted to lock said adjusting means when the hatching device is operated.

WILHELM STAHL. 

